1. Field of the Invention
The present invention relates to an optical pulse testing device for use in measuring various properties of an optical fiber to be measured, on the basis of a returned light of an optical pulse that is obtained from the optical fiber to be measured.
2. Description of the Related Art
As well known in the art, an optical pulse testing device is a device for detecting a back scattered light and a reflected light at each point where an optical pulse passes through in an optical fiber to be measured, to measure various properties of the optical fiber to be measured. In one of the optical pulse testing devices, it is known to detect returned lights whose wavelengths are different from one another, in order to measure a particular property. Inasmuch as propagation rate is dependent on the wavelength of each light in the optical fiber to be measured, returned lights whose wavelengths are different from one another are returned back from points (return points) which are different from one another, when the returned lights are detected at a time. As a result, it is impossible to exactly detect the properties of the optical fiber to be measured, inasmuch as error occurs in each of the return points in case of detecting the returned lights whose wavelengths are different from one another, at a same time.